Combustion properties of laboratory-made black liquors

Combustion behaviour of black liquors has been measured by a single droplet burning technique. The liquor samples originated from different stages of kraft, kraft-AQ, and soda-AQ pulping of softwood and hardwood. One series of cooking liquors was also made by delignifying wood after removal of extractives. Different liquors showed great differences in their combustion properties. Swelling under the combustion conditions studied increased with cooking time for most liquors. The removal of extractives from wood before delignification did not significantly affect the burning behaviour of liquor in comparison to liquor from unextracted wood